Hardly more than a year ago, just asking your desktop computer dealer for a PC with "Intel inside" was enough to ensure you were getting the best available PC processor within your budget.

But with AMD Corp., a manufacturer of computer processors, having made terrific strides in the business-PC and high-end computer markets, Intel is no longer the only game in town.

To get you up to speed, here is a list of the types of processors you'll find in the current processor market.

Pentium 4. Just released by Intel this past November, it's currently available at speeds of 1.4 and 1.5 gigahertz (GHz). The Pentium 4 processor is aimed at the extremely high-end portion of the computer market, particularly for workstations, and it will probably take some time before it is worked into the mainstream.

Pentium III. Though Intel has released a newer version of the Pentium, you can still expect to find Pentium III processors in most of today's high-end business computers over the next few quarters. With speeds that range from 450 to 933 megahertz (MHz), the Pentium III still delivers top-notch performance for most business users' needs.

Pentium II. Bargain hunting? Ask your computer dealer if he has systems with Pentium II processors he'd like to get off his hands. Though no longer manufactured by Intel, older systems that contain this Pentium III predecessor will do just fine for general office applications.

Athlon. Competing against Intel's Pentium III is AMD Corp.'s Athlon chip. It is available in speeds that range from 850 MHz to 1.2 GHz, and has performed very well in tests against the Pentium III. Computer manufacturers currently using AMD's Athlon chip include Gateway, Compaq, and Hewlett-Packard (these companies use Intel chips in other systems as well).

Celeron. Many budget PCs - typically priced less than $1,000 - use Intel's Celeron processor. This chip ranges in speed from 500 to 733 MHz. Celeron chips are designed with less performance level than the Pentium chips so the computers that contain them are aimed more at the home and college dorm environment rather than the workplace. But a computer with a Celeron chip would also be perfectly suitable for any employee who uses a computer only for light office tasks such as scheduling and data entry.

Duron. Another AMD product, this processor - meant for budget PCs - was released last September with available clock speeds of 700 MHz and 750 MHz. Designed to compete directly with Intel's Celeron, this chip has performed very well in comparability tests.